of the characteristic thoughts and feelings of a large mass of our humanity during a long period of history.
The student of the architecture of these churches-likewise labours under serious disadvantages. Turkish colour-wash frequently conceals what is necessary for a complete survey ; while access to the higher parts of a building by means of scaffolding or ladders is often impossible under present circumstances. Hence the architect cannot always speak positively^ and must leave many an interesting point in suspense.
Care has been taken to distinguish the original parts of a building from alterations made in Byzantine days or since the Turkish conquest; while5 by the prominence given to the variety of type which the churches present3 the life and movement observable in Byzantine ecclesiastical art has been made clear? and the common idea that it was a stereotyped art has been proved to be without foundation.
Numerous references to the church of S. Sophia occur in the course of this volume^ but the reader will not find that great monument of Byzantine architectural genius dealt with in the studies here offered. The obstacles in the way of a proper treatment of that subject proved insuperable3 while the writings of Salzenberg, Lethaby5 and Swainson5 and especially the splendid and exhaustive monograph of my friend Mr. E. M. Antoniadi3 seemed to make any attempt of mine in the same direction superfluous if not presumptuous. The omission will3 however^ secure one advantage : the churches actually studied will not be overshadowed by the grandeur of the c Great Church/ but will stand clear before the view in all the light that beats upon them.
I recall gratefully my obligations to the Sultan's